The goal of this project is to develop efficient and general synthetic methods for the stereospecific synthesis of anticancer sesquiterpene lactones, in particular, vernolepin and vernomenin. In this regard, we hope to use our recently developed method for preparation of alpha-carbalkoxy-gamma-alkylidene-delta alpha, beta- butenolides; these will function as methyl vinyl ketone mimics in a ring annelation sequence. Bibliographic references: A.G. Schultz, "Heteroatom Directed Photoarylation. A New Method for Introduction of Angular Carbon-Carbon Bonds," J. Org. Chem., 39, 3185 (1974). A.G. Schultz and R.D. Lucci, "Heteroatom Directed Photoarylation. Photochemistry of Aryloxyenones, "J. Org. Chem., 40, 1371 (1975). A.G. Schultz, "A Selenocarbonyl Ylide. Photogeneration and Rearanagement, "J. Org. Chem., submitted for publication.